Materials Science and Engineering Calendar

Recent developments in electron ptychography, a phase-retrieval approach computational imaging technique, have allowed for sub-angstrom resolution imaging in uncorrected electron microscopes without the high cost associated with hardware-based aberration-correction. Sub-0.5-angstrom resolution has been demonstrated in twisted 2D materials systems in uncorrected STEMs using single-slice electron ptychography. Here, we demonstrate multislice electron ptychography on a commercially available uncorrected STEM over a range of materials systems with sub-angstrom in-plane resolution and few-nm depth resolution. Multislice electron ptychography (MEP) allows for the retrieval of the 3D structure of the sample by dividing the sample into a series of slices. First, we benchmark the performance both laterally and in depth of MEP on twisted bilayer WSe2. Next, we evaluate the performance of MEP on typical classes of TEM specimens, such as 5 nm SrTiO3 and gold nanoparticles. Across a range of samples, we attain a lateral resolution of below 1 Å, indicating the broad potential applicability of MEP for sub-angstrom resolution electron ptychography in uncorrected STEMs.